Patent GB-701558-A (GB)
Title: Self threading yarn tension device
IPC: B65H59/10
Filed: 1951-12-29
Abstract: 701,558. Winding bobbins; tensioning  arrangements &c., EVANS O (Foster Machine Co). Dec. 29. 1951, No. 30394/51. Class 120(2) A self-threading yarn tensioning mechanism comprises a yarn guiding eye positioned above the upper end of a supply bobbin in yarn feeding position, yarn being drawn from the bobbin through the yarn guide by a package on which yarn is wound beyond the yarn guides, a yarn tensioning device having an open side through which yarn mav be introduced into the tensioning device as the yarn lies in its normal feeding path from the yarn guide to the winding package, a second yarn guiding member overling the yarn tensioning device and extending laterally thereof, resilient means co-operting with an elongated portion of the yarn guiding means to form a resiliently closed slit, means for delivering a knotted yarn to the slit with the knot above the slit, the under side of the yarn guiding member providing a free passageway from the slit to the yarn guide and yarn tensioning device; whereby the yarn is pulled through the slit and is delivered to the open side of the tensioning device by the running of the yarn. The mechanism is mounted on the upper end of an inclined rod 11 attached to the frame 10 of an automatic winding machine. A member 12 carrying two radially pivoted supports 14 is rotatably mounted at the lower end of rod 11. A pinion 20 attached to the support 12 is rotated by a rack 22, half a revolution at a time so that a full bobbin placed on the right hand support, Fig. 1, may be brought to a position diametrically opposite, Fig. 11. The travelling rack forms part of a tender which carries a knotting device to unite the trailing yarn from the unwinding bobbin to the leading yarn from the fresh bobbin. The frame 10 is additionally supported.on the winding machine by a strut 24. Yarn is unwound from the bobbin in the left hand position, Fig. 11, passing through a guide eye 61, a tension device 65, 71, a slub catcher 74 and over a lever 80 which it holds depressed. The upper member 71 of the tension device is weighted by removable washers 72. When the tension in the unwinding yarn is diminished, the lever 80 rises and actuates a mechanism to stop the winding machine. During the rotation of the bobbin supporting member 12. a cam 18 moves the member 14 radially to an inclined position and ejects the bobbin. A full bobbin is placed upon the right hand support, Fig. 1. being guided into position by a member 40 comprising two hinged parts, one of which is moved out of position as the full bobbin is moved towards the winding, position. The leading end of the yarn from the full bobbin, in the position shown in Fig. 1 is conducted over a guide 44 to a clamping device 34, 36. A suction device upon the advancing knotter draws the trailing end of the unwinding yarn also into the clamp as seen in Fig. 1. Stops 46, 47 cause the knotter to work and unite the yarns and sever the surplus ends. Continued advance of the knotter brings the full bobbin into the position shown in Fig. 11. To arrive at this position, the knotted yarn slips off the end of guide 44 and travels along a plate edge 59 forming part of a slot 60 and also over the downwardly inclined end of a wire member 53, the knot travelling upwardly alnog the wire 53. The forward end of the yarn F now being drawn to the winder passes along the edge of a member 50 against which it is pressed by the spring-urged member 53, so providing the initial tension to tighten the knot. Continued advancement of the bobbins causes the yarn to slip off the end of 50 and assume the position shown in Fig. 11. As it slips off, the yarn enters a slubcatching device 73, 74, Fig. 6. The upper member 74 is integral with a resilient member 75, Fig. 1, attached at one end to the frame 30, a screw 77 being provided at the other end to vary the gap. A plurality of bobbin holders may be provided in parallel rows on opposite sides of the automatic winding machine, a single knotting tender operating successively on each unit, first on one side of the machine and then on the other. Specifications 598,596 and 684,812 are referred to.